UCL Quantum Technologies

By using a scanning tunnelling microscope, Steven Schofield's group have created precise arrays of atomic defects on a silicon surface and demonstrated that they couple to form unique and interesting quantum states. The next step is to replicate these results in other material systems which holds particular interest for quantum devices fabrication.

Area laws for entanglement in quantum many-body systems give useful information about their low-temperature behaviour and are tightly connected to the possibility of good numerical simulations. In joint work with Michal Horodecki from Gdansk University, Fernando Brandao proved that for one dimensional quantum states an area law always holds true whenever there is a notion of correlation length.

Qubits (quantum bits) can be visualised as an octahedron inside a sphere. The symmetries of the octahedron represent important quantum operations in quantum computing, so-called Clifford group gates, which can be achieved fault tolerantly. Dan Browne's group in collaboration with former group member Earl Campbell (creator of this image) are developing new approaches to fault tolerance in quantum computation.

Progress in quantum technologies is at an exciting stage. Applications that harness the non-classical features of quantum mechanics to perform tasks hard or impossible with conventional technologies are now reaching beyond the laboratory into industrial development. Some of these, such as quantum cryptography and communication have already arrived in the marketplace, while others – such as quantum computation – remain a significant technological challenge, but all have the potential to bring revolutionary advances compared to their classical counterparts.

Even in conventional information technology hardware, quantum mechanics is becoming increasingly important, as Moore’s law pushes ever greater miniaturization. Quantum phenomena are at the heart of fields like molecular electronics and nano-spintronics, which represent the ultimate limit of IT miniaturization. Even more strikingly, quantum effects may play a crucial role in important biological processes such as photo-synthesis and bird navigation. This places the transformative potential of quantum technologies at centre stage – research in this area today will drive industry forward tomorrow.

To achieve this exciting potential, a multi-disciplinary research effort incorporating both theoretic and experimental progress is vital. UCL is a centre of excellence in quantum technologies with an unrivalled breadth of expertise, from fundamental theory to industry-linked experiment.